The Word Assume Makes and As* out of You and Me

A special someone was mad at me for assuming that he had gotten into a fight with my friend. He was extremely mad at me, and after a long phone argument he hung up on me, and a while later sent me this text: "The word assume makes an as* out of you and me."

So, I responded saying:

I'm sorry I flipped out and assumed that. I was worried because I didn't want to do anything wrong but that wasn't a wise move and that's not an excuse. I don't want this go over in our friendship though, because you really mean a lot to me and I don't want to lose you... Just being honest.

And he responded with a smiley face, which is definitely a positive remark after being so angry towards me earlier.